1. Field of the Invention
The present invention relates to a control device of a mechanism that stores and/or reproduces data on a storage medium provided in a magnetic disc device or the like.
2. Description of the Related Art
Generally, a magnetic disk device is configured in such a way in which a magnetic head (swing arm) is floated by approximately 0.01 μm to 0.02 μm by means of a stream of air caused by rotating a magnetic disk at high speed.
Recently, as the density of the recording surface of magnetic disks has increased, the flying height of magnetic heads have become increasingly lower.
Accordingly, the magnetic head's flying height is now easier to affect due to changes in atmospheric pressure, temperature, or other variations. For example, when the atmospheric pressure increases, the flying height of the magnetic head also increases, and, accordingly the signal characteristic deteriorates. When the atmospheric pressure decreases, the flying height of the magnetic head decreases in response and the probability that the magnetic head touches and damages the magnetic disk is greater.
In other words, there has been a problem in which a characteristic of a signal stored and/or reproduced on the magnetic disk is affected by the changes of the atmospheric pressure, temperature, or other variables.
Japanese Patent Application Publication No. 63-069075 discloses a magnetic disk device that increases the recording surface density while reducing the risk of impact between the magnetic head and the disk by decreasing the flying height of the magnetic head only at times when data is in the process of being stored and/or reproduced.
Japanese Patent Application Publication No. 06-236641 discloses a head flying height control device that controls the flying height of the head of a disk driving mechanism by dynamically adjusting a read/write head suspension system in real time.
Japanese Patent Application Publication No. 2002-092810 discloses a magnetic disk device that improves an error recovery ratio by changing the flying height of the magnetic head in accordance with error causes.